I think it is pretty well accepted that the AKG's SOUND better than the Dt880s.
BUT, the DT880s are definitely much more COMFORTABLE.
I've tried both on, and the headband on the AKG is just ridiculous. One of my friends resorted to wrapping a towel around his to make it more comfortable.
Although, maybe this model is different?
The_CobrajThe previous AKGs in the 7xx series (Q701s, K701s and the 702s) had little 'bumps' on the underside of the headband / leather strap. A lot of people find them uncomfortable.
The K712 does not have this issue- the headband is a different design and by all accounts they're very comfortable.